Note 1 - Summary of Operations and Significant Accounting Policies 1 (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2025 USD ($) shares	Dec. 31, 2024 USD ($) shares
Capitalized Contract Cost, Gross \| $	$ 0	$ 0
Research and Development Expense, Gross \| $	12,079	9,549
Customer Funded Research and Development Expense Included in Cost of Goods Sold \| $	$ 1,681	$ 1,281
Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements	0	212,197
Number of Operating Segments	2
Share-Based Payment Arrangement [Member]
Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements	0
Share-Based Payment Arrangement, Option [Member]
Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements		770,376
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	967,351	336,060
Restricted Stock [Member]
Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements		38,386
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	40,343
Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
Number of Major Customers	1	1
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| Large Defense Primary Contractor, 1 [Member]
Concentration Risk, Percentage	27.00%	23.00%
Customer Concentration Risk [Member] \| Revenue Benchmark [Member] \| Large Defense Primary Contractor, 1 [Member] \| Battery & Energy Products Segment [Member]
Concentration Risk, Percentage	29.00%	24.00%
Minimum [Member]
Standard Product Warranty, Period	90 days
Maximum [Member]
Standard Product Warranty, Period	3 years
Extended Warranty Contracts [Member]
Extended Product Warranty, Period	8 years
Revenue, Remaining Performance Obligation, Amount \| $	$ 855
Certain Communications Systems Products [Member]
Contract with Customer, Liability, Revenue Recognized \| $	$ 298	$ 298

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The gross costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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